Linq 分组查询

 根据部门分组 ,然后存储部门下所有员工

 public class Custom
    {
        public string dname { get; set; }
        public List<Employees> lis { get; set; }
    }
    public class Employees
    {
        public string id { get; set; }
        public string name { get; set; }
        public string depart { get; set; }
    }
static void main()
{
DataTable dt = new DataTable();
                dt.Columns.Add(new DataColumn("id"));
                dt.Columns.Add(new DataColumn("name"));
                dt.Columns.Add(new DataColumn("depart"));

                string[] s = { "1,a,.net", "2,b,.net", "3,c,.net", "4,h,ui", "5,i,ui", "6,j,ui" };
                foreach (string p in s)
                {
                    DataRow dr = dt.NewRow();
                    dr[0] = p.Split(',')[0];
                    dr[1] = p.Split(',')[1];
                    dr[2] = p.Split(',')[2];
                    dt.Rows.Add(dr);
                }
              
                var item = from p in dt.AsEnumerable()
                           group p by p.Field<string>("depart") into d
                           select new Custom
                           {
                               dname = d.Key,
                               lis = dt.AsEnumerable().Where(a => a.Field<string>("depart") == d.Key)
                                      .Select(a => new Employees { id = a.Field<string>("id"), name = a.Field<string>("name"), depart = a.Field<string>("depart") }).ToList<Employees>()
                           };
}